1. Field of Invention
The present invention relates to a booster cable for a vehicle battery, and more particularly to an adaptive booster cable that is capable of detecting the polarities of two interconnected batteries and automatically switching the connection relationship between the two batteries to ensure the batteries are safety connected when jumping a battery.
2. Related Art
Generally, a battery can provide the operating voltage to all electrical devices installed in a vehicle and to start the vehicle engine. Although most vehicles are now equipped with a meter to indicate the charge on the battery, the battery can still be totally discharged due to carelessness of the driver.
A frequent reason for discharging the battery is that the driver forgets to turn off the vehicle lights after turning off the engine. W then the lights are turned on for a long time without running the engine, the lights will continuously drain electricity from the battery. Another reason for a dead battery is that the battery has reached the end of its useful life. As a battery is used, the battery gradually ages and eventually will no longer hold a charge. Notwithstanding the reason for a dead battery, a dead battery represents a serious problem in that the car engine cannot be started with the dead battery. A temporary solution to the problem is to xe2x80x9cjump startxe2x80x9d the vehicle engine from another, fully charged battery. The two batteries are often electrically connected by a booster cable.
The conventional booster cable is composed of pair of cables. Each cable has two ends, and a clip is attached to each end. The clips on each end of the pair of cables are intended to respectively connect to two poles of a battery. Generally, the clips on one end of the pair of cables are different colors, and the clips on the ends of the same cable are the same color, such as red and black, for polarity recognition. When the booster cable connects two batteries, the positive poles must be connected to each other, and the negative poles must be connected to each other. Failure to recognize the correct polarity by connecting the colored clips to the wrong poles is distinctly possible and can cause catastrophic damage, such as an explosion.
To overcome the shortcomings, an adaptive booster cable for a vehicle battery in accordance with the present invention obviates or mitigates the aforementioned drawbacks.
The primary objective of the present invention is to provide an adaptive booster cable to automatically detect the polarity relationship of two interconnected batteries and to appropriately switch the connection between the two batteries based on the detected polarity on each clip.
To achieve the objective of the present invention, an adaptive booster cable is connected between two vehicle batteries. Each battery has a positive and a negative pole. The adaptive booster cable comprises a first pair of clips, a second pair of clips, a polarity detecting unit, a switching unit, a current detecting unit and a power supply unit. The two clips in each pair are respectively connected to a positive terminal and a negative terminal on a battery so each clip has a different polarity. The polarity detecting unit connects to each clip to detect the polarity of each clip. The switching unit connects the two pairs of clips. The switching unit appropriately switches the connection between the clips of each pair based on the polarity detected by the polarity detecting unit. The current detecting unit mounted between the two pairs of clips to monitor whether any clip disconnects from the battery. The current detecting unit provides a circuit continuity signal to the polarity detecting unit. The power supply unit provides an operating voltage to the polarity detecting unit.
After the two pairs of clips are respectively connected to the two batteries, the polarity detecting unit detects the polarity of each clip and outputs a control signal to the switching unit generate the correct connection between the two batteries.
Other objectives, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.